Rainwater tank



FIG. 1 is a perspective view of the rainwater tank;

FIG. 2 is a right side elevation view of the rainwater tank;

FIG. 3 is a left side elevation view of the rainwater tank;

FIG. 4 is a rear elevation view of the rainwater tank;

FIG. 5 is a front elevation view of the rainwater tank;

FIG. 6 is a plan view of the rainwater tank; and,

FIG. 7 is a bottom view of the rainwater tank. 

The ornamental design for a rainwater tank, as shown and described. 